For that purpose, this article introduces the formal notion of the family of alpha-shapes of a finite point set in R3. Each shape is a well-defined polytope, derived from the Delaunay triangulation of the point set, with a parameter alpha is-an-element-of R controlling the desired level ...
Three-Dimensional shape measurement has been confronted with the ambiguity on the steep surface. To address the problem, compressed sensing theory is employed to reconstruct phase shifting images in DMD camera. Specially, every CCD pixel in the region of interest is aligned to N × N DMD mi...
For that purpose, this paper introduces the formal notion of the family of $\\alpha$-shapes of a finite point set in $\\Real^3$. Each shape is a well-defined polytope, derived from the Delaunay triangulation of the point set, with a parameter $\\alpha \\in \\Real$ controlling the ...
Several mediators, such as prostaglandin E2 (PGE2), tumor necrosis factor-alpha stimulated gene-6 (TSG-6), galectin-1 (GAL-1), TGF-β1, and IL-6, are produced by BMSCs upon inflammatory stimulation. BMSCs in the SE-25T-2D group significantly upregulated the expression of GAL-1, TSG...
Supporting this hypothesis, the voltage trace possesses the same general shape as with Mg substrates, lacking any plateaus early in the plating period that might indicate a phase transformation (Figure S3). As a caveat, it is important to note that subtle differences in surface roughness, crystal...
如同图像的特征一样,我们需要使用类似的方式来描述三维点云的特征。 常用的特征描述算法有:法线和曲率计算、特征值分析、PFH、FPFH、SHOT、VFH、CVFH、3D Shape Context、Spin Image等。PFH:点特征直方图描述子,FPFH:跨苏点特征直方图描述子,FPFH是PFH的简化形式。
点云配准的概念也可以类比于二维图像中的配准,只不过二维图像配准获取得到的是x,y,alpha,beta等放射变化参数,三维点云配准可以模拟三维点云的移动和对齐,也就是会获得一个旋转矩阵和一个平移向量,通常表达为一个4×3的矩阵,其中3×3是旋转矩阵,1x3是平移向量。严格说来是6个参数,因为旋转矩阵也可以通过罗格里德斯...
Finally, the vascular scaffolds presented tubular shape was formed and the cross-section was observed by SEM. 2.7. Porosity measurements The porosity of 3D microspheres-nanofiber scaffolds and SF freeze-dried scaffolds were detected using liquid displacement [37]. Hexane as the displacement liquid was...
“p” above) into a mesh buffer. These old vertices may be explicitly referenced when the old vertex is again needed. This approach provides a fine control that supports irregular meshes of nearly any shape. As used herein, the term “mesh buffer” shall refer to this queue, and the ...
FIG. 7D is a graph of alpha value verses position of a calibration target. The highest derivative position will point to the position of the center and identify the location of the receptive field610in the first direction and/or second direction. Accordingly, the x and y coordinates of the ...